1. Technical Field
This disclosure relates to an inspection apparatus, by which flux attached to a part of an object to be inspected is removed, and an electrical connection member is brought into contact with the part to be inspected. Thus, reliable inspection of the object can be performed.
2. Description of the Related Art
Conventionally, for electrical inspection of a printed substrate which has electronic parts mounted thereon, an inspection apparatus which has a contact pin of a contact type forming its end shape is often used. The contact pin, for example, is formed from an electrical conducting material, and a sharp needle which forms the end shape of the contact pin is stored in a sleeve, and the contact pin is biased by a spring to be moved toward an object to be inspected.
In the inspection apparatus, a plurality of contact pins are arranged corresponding to parts to be inspected of the printed substrate, for example, electrode parts or lead soldered portions of the electronic parts, etc. And when carrying out the inspection, a flux film formed on a surface of the substrate during processing, such as a reflow process, is broken through and removed by pressing a needle end of each of the plurality of contact pins against the printed substrate, and then the needle end is brought into contact with the respective part to be inspected, and electrical connection is achieved. And thus, detection of, such as defects of the soldered portions, or damage of the electrical parts, or unmounted parts, is carried out by processing electric signals obtained by the contact pins with an electric circuit in the inspection apparatus.
JP 2002-90386 A proposes a structure of a contact pin to reliably remove a flux film attached to a printed substrate.
In the conventional inspection which employs the contact pin, if the flux is not removed with the contact pin, an inspection error occurs due to defective conduction. In addition, when the flux attaches or accumulates at the end part of the needle when repeating the inspection, or the flux film is not removed completely due to variability of a thickness of the flux film, etc., defective conduction is caused between the contact pins and the parts to be inspected. Therefore, in the inspection operation, the inspection begins after moving the contact pins to the object to be inspected and removing the flux.
The contact pin described in JP 2002-90386 A is structured such that, to remove the flux reliably, a needle stored in a sleeve is movable axially, first and second springs, a supporting member, an inclining member which maintains a leaning posture, a third spring and a receiving member are arranged at the needle, and when pressing an end of the needle against the printed substrate, the inclining member moves with an operation of the needle and is guided by an inner wall surface of the sleeve to be in a vertical posture, and under such a condition, a pin provided on the inclining member in a protruding condition is inserted into a hole of the receiving member by the second spring, and the members collide mutually through the closely-attached third spring, and the impact strength is added to the needle.
For the contact pin described in JP 2002-90386 A, due to a movable structure which includes a plurality of members being provided in the pin, problems arise such as, for example, an increase of the manufacturing cost, variability of product features and occurrence of defective behavior due to the complexity of the structure.
In addition, in the conventional inspection process, for example, as illustrated in a flow chart of FIG. 22, an operator sets the printed substrate which is the object to be inspected to a predetermined position (S101), by moving the contact pin from a standby position to come into contact with the printed substrate (S102), the flux attached to the part to be inspected is removed (S103), and when it is determined that the flux is satisfactorily removed for an inspection (OK of S103), the predetermined inspection is started in a state where the contact pin comes into contact with the printed substrate (S104).
When an inspection operation is started in step S104, a power source of the inspection apparatus is turned on (S106), and an electrical inspection on the printed substrate is started (S107), and by an inspection judgment (S108), judgments of a good item (OK) and a defective item (NG) are made (S109). Processes of steps S106-S109 are carried out automatically by control judgments of a computer, for example.
However, when the operator judges that the flux is not removed completely (No of S103), the contact pin is moved away from the part to be inspected (S105), and again the contact pin is moved from the standby position to come into contact with the printed substrate (S102), and after the flux attached to the part to be inspected is removed (S103), the inspection processes after step S104 are carried out.
The processes of S101-S105 are performed by manual operations of the operator, and it is necessary to move the contact pin up and down many times to remove the flux reliably, depending on a state of the flux. Therefore, a problem arises in that the inspection takes more time, i.e., a time for removal of the flux.